Preparation and characterisation of green clay-polymer nanocomposite for heavy metals removal

ABSTRACT

Natural polymer Moringa oleifera seed as coagulant and bentonite clay as adsorbent were used for preparing novel composite coagulant. Results obtained from FTIR, SEM, TEM and P-XRD show that the bentonite clay and M. oleifera seed biopolymers physico-chemically interact with each other during the preparation of clay-polymer composite. The FTIR results show that the major functional groups present in bentonite clay and M. oleifera seed are integrated at nano levels in the novel composite to remove heavy metals from aqueous systems. The coagulo-adsorption using clay-polymer composite may be used for the adsorption of heavy metals ions from the aqueous systems. It becomes possible due to the structural characteristics of the clay crystallites together with the functional attraction of the biopolymer and it results in the formation of clay-polymer metal complexes. The clay-polymer nano-composite of M. oleifera seed and bentonite clay showed considerable cadmium, chromium and lead removal property.

KEYWORDS:

• Hazardous heavy metals
• clay-polymer nanocomposite
• coagulo-adsorption
• cadmium removal
• chromium removal
• lead removal

Acknowledgements

The authors thank the Founder Director Late. Dr. P. K. K. Nair, President Dr. G. Madhavan Nair, Director Dr. G. Achuthan Nair and Principal Scientist & Deputy Director Dr. Shaji P. K of Environmental Resources Research Centre (ERRC), Thiruvananthapuram for the constant support rendered during the course of this research work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes on contributors

Ravikumar K is a Ph. D Research Scholar of Mahatma Gandhi University, Kottayam, India and currently working as an Assistant Executive Engineer at Kerala Water Authority, Thiruvanthapuram, India. His research interest is eco-friendly water treatment using natural composite materials.

Udayakumar J is an Assistant Professor in the Department of Civil Engineering, TKM College of Engineering, Kollam, India. His research interests are Environmental Geology and water treatment.

ORCID

K. Ravikumar http://orcid.org/0000-0002-7121-3308

J. Udayakumar http://orcid.org/0000-0003-0286-5836

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.